/*
    This file is part of Sylvan.
    Copyright (C) 2008-2018 Cute Chess authors
    Copyright (C) 2019 Wilbert Lee

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Sylvan.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef AUTO_VERTICAL_SCROLLER_H
#define AUTO_VERTICAL_SCROLLER_H

#include <QObject>

class QAbstractItemView;

/*!
 * \brief Automatically scroll an item view when new items are added.
 *
 * AutoVerticalScroller automatically scrolls an item view vertically when
 * new items are added. Automatic scrolling only happens when the scroll bar
 * is positioned at the bottom and thus the user has always control of the
 * behavior.
 */
class AutoVerticalScroller : QObject
{
    Q_OBJECT

public:
    AutoVerticalScroller(QAbstractItemView* view, QObject* parent = nullptr);

private:
    QAbstractItemView* m_view;
    bool m_scrollToBottom;

private slots:
    void onRowsAboutToBeInserted();
    void onRowsInserted();

};

#endif // AUTO_VERTICAL_SCROLLER_H

